I’m often rebooting my Mac into a different OS, then returning to Mac OS to continue with a multi-window, multi-tab project in ST3, spread across multiple desktops (or what Apple calls ‘Spaces’).
It would be a very very welcome feature for my ST3 windows to re-open on the Space they occupied before I logged out 
Many apps do this, so I imagine it’s a fairly simple thing to add…?
Also: great editor! 